The present invention relates to a magnetic disk drive and, more particularly, to a magnetic disk drive capable of preventing dust-containing air from standing around the inner periphery of a magnetic disk.
It is a common practice with a magnetic disk drive to support a magnetic head on an arm and move the head substantially in the radial direction of a disk mounted on a spindle. As the disk spins, a stream of air is generated between the disk and the head to cause the head to float a small distance away from the disk. In this condition, desired data is recorded in or reproduced from the disk.
However, the conventional disk drive described above has a problem that since the stream of air is generated at the side where the arm supporting the head is located, it entangles dust existing between the head and the disk and in the vicinity of a positioner therein while flowing toward the inner periphery of the disk, i.e., toward the spindle. As such dust-containing air stands around the spindle, while dust is apt to deposit on the disk and is likely to damage it particularly when the disk drive is started up. Another problem is that the dust cannot be removed efficiently since the head is moved by the arm substantially in the radial direction of the disk, changing the path of the air stream every moment.
To absorb the dust around the disk, there has been proposed to arrange an electrostatic filter or similar implement around the spindle, as taught in, for example, Japanese Utility Model Laid-Open Publication (Kokai) No. 62-61099 and Japanese Patent Laid-Open Publication No. 2-185785. However, even the filter scheme is not fully satisfactory since the relative position of the head to the disk in the radial direction of the disk changes, changing the path along which air flows.